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Co-authored-by: Victor Stinner <vstinner@python.org>

Author: corona10

Doc/library/mmap.rst

@@ -330,12 +330,12 @@ To map anonymous memory, -1 should be passed as the fileno along with the length
 
    .. method:: set_name(name, /)
 
-      Annotate the memory map with the given *name* for easier identification
+      Annotate the memory mapping with the given *name* for easier identification
       in ``/proc/<pid>/maps`` if the kernel supports the feature and :option:`-X dev <-X>` is passed
       to Python or if Python is built in :ref:`debug mode <debug-build>`
       The length of *name* must not exceed 67 bytes.
 
-      .. availability:: Linux >= 5.17
+      .. availability:: Linux >= 5.17 (kernel built with `CONFIG_ANON_VMA_NAME` option)
 
       .. versionadded:: next
 

Doc/whatsnew/3.15.rst

@@ -582,7 +582,7 @@ mmap
   (Contributed by Serhiy Storchaka in :gh:`78502`.)
 
 * Added the :meth:`mmap.mmap.set_name` method
-  to annotate an anonymous memory map
+  to annotate an anonymous memory mapping
   if Linux kernel supports :manpage:`PR_SET_VMA_ANON_NAME <PR_SET_VMA(2const)>` (Linux 5.17 or newer).
   (Contributed by Donghee Na in :gh:`142419`.)
 

Lib/test/test_mmap.py

@@ -1176,12 +1176,12 @@ def test_set_name(self):
 
         # Test name length limit (80 chars including prefix "cpython:mmap:")
         # Prefix is 13 chars, so max name is 67 chars
-        long_name = 'x' * 30
+        long_name = 'x' * 67
         result = m.set_name(long_name)
         self.assertIsNone(result)
 
         # Test name too long
-        too_long_name = 'x' * 80
+        too_long_name = 'x' * 68
         with self.assertRaises(ValueError):
             m.set_name(too_long_name)